Iain Martin is a political commentator, and a former editor of The Scotsman and former deputy editor of The Sunday Telegraph. He is the author of Making It Happen: Fred Goodwin, RBS and the men who blew up the British economy, published by Simon & Schuster.. As well as this blog, he writes a column for The Sunday Telegraph. You can read more about Iain by visiting his website

Selfie-gate: Why do Cameron and Obama feel the need to behave like idiots?

David Cameron is a well brought up son of the English shires. He knows, I suspect, not to talk too loudly in church, not to help himself to the claret when invited to a dinner party and not to be rude to waiters or waitresses. He can be a bit presumptuous and thoughtless with his own MPs, which may one day have consequences. But that aside, he knows how to behave.

So why did a grinning Prime Minister today lean in to be in a "selfie" with President Obama and the leader of Denmark? She's Neil Kinnock's daughter-in-law, by the way. A dignified Michelle Obama looked straight ahead and refused to indulge in such ridiculous teenage antics at what, after all, was a memorial service for Nelson Mandela.

For those unaware of the concept of a "selfie", it is a picture taken of yourself on a mobile telephonic device. A picture of the Cameron/Obama selfie being taken has emerged on the internet.

It is only yesterday that Cameron was caught during the tributes to Mandela in the Commons tweeting a picture of "little Ant'n'Dec" (small television characters who resemble the real Ant and Dec, the well-established Geordie entertainers). It seems one of his staff tweeted it, thus undermining his efforts at creating the impression of authenticity.

What on earth is going on? Why do world leaders now behave like this? And at a memorial service?

Perhaps it is just that the current generation – my generation – is so appallingly spoiled that basic notions of decorum have been shot to pieces. The materialistic search for self-gratification trumps all. Why let a fuddy-duddy thing like manners get in the way of a social media opportunity, where we can put ourselves at the centre of everything, clowning around like muppets watching a Lady Gaga concert, grinning at the camera and then tweeting the results.

But I banish that thought. In all manner of jobs and professions are people who would not behave like Obama and Cameron did today on work time, partly because they just wouldn't. And partly because they know that they might get fired for tweeting a grinning selfie from inside the recently-departed CEO's memorial service.

And that's the thing about parts of the the current leadership class and their attempts to prove they are in touch and just like us. Ironically, such efforts risk making them look spoilt, as though they have their own set of rules.

Alert readers will notice that I first saw the picture in question on Twitter, so perhaps I am in a small way complicit in the whole mad business. But I'm not running the country (thank God) or representing Britain abroad. I am a journalist, and journalists do stupid stuff like look at Twitter. It's now part of the job. But making a fool of yourself on Twitter should definitely not be a core element of the Prime Minister's activities.

The sadness is that Cameron is good abroad. I for one have never looked at images of him on a trip and felt embarrassed or baffled by his behaviour, beyond some concerns about his crawling to the Chinese last week . But I saw that selfie picture and my response was simple and from the gut: what the hell do you think you're doing man? Whatever it is stop it.